Monoazo compounds containing a pyrazolone nucleus



Patented Apr. 20, 1948 2,439,798 MONOAZO COMPOUNDS CONTAINING PYRAZOLONENUOLEUS Joseph B. Dickey and John R. Byers, Jr., Roches ter, N. Y., andJames G. McNally, Oak Ridge, Tenn., assignors to Eastman Kodak Company,Rochester, N. Y., a corporation of New Jersey No Drawing. ApplicationJanuary 21,1944, Serial No. 519,192"

1 Claim. (01. 260-163) This invention relates to monoazo compoundscontaining a pyrazolone nucleus and to ajprocess for preparing them.

A number of acid dyes which are mon'oazo compounds containing apyrazolone nucleus have been known for many years and have been'used todye wool or to prepare color lakes. It has'also been proposed to dyecellulose esterrayon with 'nonsulfonated monoazocompounds containing apyrazolone nucleus ofthe following formula:

(7/ CH I Such monoazo compounds, however, dye cellulose ester rayon onlyat low rates of speed at the ordinary dyeing temperatures, Subsequently,it was proposed to dye cellulose ester rayon with monoazo dyescontaining a-pyrazolone nucleus of the following formula:

However, such pyrazolone dyes have low tinctorial power, but are usefulfor tinting cellulose wherein Z represents hydroxyl, amino or alkoxyl,have been developed on cellulose ester rayon by applying an aminoazocompound to the'rayon, dlazotizing and coupling on the rayon with apyrazolone corresponding to the nucleus formulated immediately above.Monoazo compounds containing a pyrazolone nucleus of the followingformula:

l C O 0 alkyl have been found to be very stable to light and to besuitable for the coloring of cellulose ester lacquers. Such monoazocompounds, however, dye cellulose ester rayon only at low rates of speedat the ordinary dyeing temperatures and are, therefore, impractical ascellulose ester rayon dyes.

We have now found a kind of non-acid monoazo compound which has not onlyvery good fastness to light, butalso can be employed to dye celluloseester rayon and fabrics made therefrom, since the compounds colorcellulose ester rayon at a practical rate of speed atlow temperatures toC.) and have a high tinctorial power for the rayon.

It is, accordingly, an object of our invention to provide new monoazocompounds and to provide a process for the preparation thereof. Anotherobject is to provide cellulose ester rayon colored with such compounds.Other objects will become apparent hereinafter.

The compounds of our invention can be represented by the followinggeneral formula:

wherein R represents a member selected from the group consisting ofhydrogen and low carbon aliphatic alcohol radicals,-R1 represents amember selected from the group consisting of carboxyl groups which areesterified with a low carbon aliphatic alcohol, a carbamyl group, acarbamyl group in which one hydrogen is replaced by a low carbonaliphatic alcohol radical and a carbamyl group in which each hydrogenatom is replaced by'a low carbon aliphatic alcohol radical, X representsa member selected from the group consisting of hydrogen, a low carbonaliphatic alcohol radical, an aliphatic ether radical, a halogen atom, atrifluoromethyl group, a cyano group, an aliphatic acyl group, acarboxyl group esterified with a low carbon aliphatic alcohol, acarbamyl group, a carbamyl group in which one hydrogen is replaced by alow carbon aliphatic alcohol radical, a carbamyl group in which eachhydrogen atom is replaced by a low carbon aliphatic alcohol radical, asulfamyl radical, a sulfamyl radical in which one hydrogen is replacedby a, low carbon aliphatic alcohol radical and a sulfamyl group in whicheach hydrogen is replaced by a low carbon aliphatic alcohol radical.

To prepare one of our new compounds, we diazotize an appropriatemonocyclic amine of the 3 4 benzene series and couple the resultingdiazoni- Example 2.4- [4- (n bu tyZ'sulfamz/Z) -2-miroum salt with theappropriate pyrazolone derivaphenylazo] --3-carbethoxy-5-pymzolone tive.The appropriate monocyclic primary amines of the benzene series can berepresented by the following formula: a 5 if C V V i V, H Q V csciior am3 N0, g v 4 NO: (3 00002135 wherein X has the value set forth above.Theappropriate pyrazolone derivatives can be tor-1 7 mulated as follows:900 cc. of nitric acid. (65%70%) in a 2-liter flask were cooled,with'stirring, to 10 to 12 C. it p r v 7 Then '75 g. of sodium nitritewere added. rapidly a in such a manner that the stirrer carried the H vcrystals immediately under the surface. Stirring I 2 I l V a N p 4 wascontinued for about 15 minutes, permitting V I I the temperature to riseto 15 to-16 C. The resultingnitrosylnitric acid solution was cooled to8' C. and 273 g. (1 mole) of 4 amino-3-nitro V gN-n-butyl'benzenesulfonamide were adde'd'porwherein R and R1 have thevalues set forth tionwise to the well-stirred solution over a periodabove. V of minutes. keeping the temperature between The followingexamples will serve to illustrate and Stirring W s co t ued at C- ournew monoazo compounds and the manner for A hour, and then 5 to 10 g. ofsodium nitrite of obtaining .the same.

were added rapidly as above. Then 100 g. of crushed ice were slowlyadded. The diazo solu- Emmpze mai tion thus prepared was added slowlywith stirring carbethoxy-fi-pyrazolone to a well-iced aqueous suspensionof 156 g. (1 mole) of 3-carbethoxy-5-pyrazolone prepared by dissolvingthe carbethoxy derivative in 1000 cc. of acetic acid and pouringthesolution into 0 two "liters of ice water with vigorous stirring.

. I Coupling was completed by adding sodium bicar- 01 N=N,-CH .1 bonate.The azo dye was filtered off, washed and dried it melted at 230 to 235c. The dye col- 0 0 yarn, greenish yellow shades.

ored cellulose acetate rayon yam,- as well as' nylon In a. mannersimilar to that illustrated in the 172.5 g. (1 mole) ofo-nitro-p-chloraniline (finely powdered) and 1000 cc. of water werevigpared:

foregoing examples. the following dyes were pre- M. P., C. orouslystirred with 0.5 g, of sodium sulfate '45 4 (4 chlom 2 mtrophenylaz 3 oftechnical oleyl alcohol, at 80 C. To this well carbamyl 5 nyrazohme218-220 stirred mixture were added 1'70 g. of sulfuric acid 4 (4 chloronitrophenylazo) 3 (spg. 1.84) in 200 cc. of water, over aperiodcarbcmethogy 5 1 225-230 of 10 minutes. 'The resulting mixture wascooled 4 nitrophenylazo) 3 carbetm and 1 kg. of crushed ice was added.Immedioxy 5 pyrgzolone 250-253 ately upon the addition'of: the ice,there was 4- (4 t iflu methy] -2 njt,ropheny1- added a solutioncontaining; 76 g. of sodium niazo) 3 carbethoxy 5 pyra-zol0ne 185-1trite in 200 cc. of water. Diazotization was com- 4 (4 carbethoxy 2nitrcphenylplete in about 15 minutes. .Excess nitrous acid 3,2 3carbethgxy- 5 pyrazo10ne 205-208 was destroyed by adding sulfamic acid.4 (4 acetyl 2 nitrophenylazo) 3 156 g. (1 mole) V of3-carbethoxy-5-pyrazolone carbqmethoxy 5 pyrazolone 254-256 were warmedin 50000. of acetic acid, and 1 kg. 4 [4 (n butyl ulfamyl) 2 nitroofcrushed ice was added'with vigorous stirring. phenylazo] 3 carbomethoxy5 The diazo solution, prepared as described above, y z l n 230-235 wasthen added. Coupling was completed by neu- 4, (4 5 methoxyethylcarbamyl2 I tralizing the mineral acid with sodium bicarnitrophenylazo) 3carbethoxy5 pybonate. The azo dye was filtered ofl, washed razolone r226-228 with water and dried. The dye colored cellu- 4 [4 3hydroxyethylcarbamyl) 2 lose acetate rayon yarn, as: well as nylon yarn,nitrophenylazo] 3 carbethoxypygreenish yellow shades from an aqueoussuspenrazolone 315 1-158 sion of the dye. The dye melted at 228 to 4 (4ethylsulfamyi 2 --nitrophenyl- 231 C- azo) 3 carbethoxy 5 pyrazoloner251-253 In place of o-nitro-p-chloraniline, a molecu- 4 (4 methoxy 2nitrophenylaz-o) larly equivalent. amount of o-nitraniline, 2- 3carbethoxy 5 pyrazolone 246-243 nitro-4-methylaniline,Z-nitro-4-methoxyaniline, 4 (4 ethoxy 2 nitrophenylazo) 32-nitro-4-ethoxyaniline, 2-nitro-4-bromaniline, 'carbethoxy -.5pyrazolone; 237-240 2-nitro-4-fiuoroaniline or. 2-nitro-4-cyanoani- 4 (4ethoxy 2' nitrophenylazo) 3 line can be used. Likewise other3-carbalkoxy-5- carbomethoxy 5 pyrazolone 244-246 pyrazolones', or3-carbamyl-5-pyrazolones, can be 4 (4 methoxy 2 nitrophenylazo) used. 73 carbomethoxy 5 -'pyrazo1one 243-245 The amines used as diazocomponents in the preparation of our new azo dyes are for the most partknown substances and can be preparedby theknown processes illustrated inthe prior-art. The amines containing a suliamyl grou can'be prepared asillustrated in the following examples:

Example 3.-4-amino-3-nitro-N-ethylbenzenesulfonamidc 1 gram-mole of4'-chloro 3 nitro-N-ethylbenzenesulfonamide and 700 cc. ofconcentra'ted'ammonia water were heated in a shaking autoclave at 160 C. for 4 hours.When cooled, the contents of the autoclave were removed and the yellowcrystals of the sulfonamide were filtered oil, washed with water anddried in the air.

The 4-chloro-3-nitro-N-ethylbenzenesulfonamide employed above wasprepared as follows: 640 g. (2.51 mole) of4-chloro-3-nitrobenzenesulfonylchloride were dissolved in 700 cc. ofacetone. The resulting solution was cooled to 3 C. To the cooledsolution were added 680 g. of a 33 per cent aqueous solution ofethylamine over a period of 2.5 hours, with stirring. Stirring wascontinued for several hours at to C. The resulting mixture was addedto 8liters of water and ice. The precipitated 4chloro-3-nitro-Nethylbenzenesulfonamide was filtered off, Washed with water and dried inthe air. It melted at 89 to 91 C. In a similar manner, other sulfonylcompounds can be prepared using ammonia, methylamine, n-butylamine,isopropylamine, phydroxyethylamine, p-methoxyethylamine,tetrahydrofurfurylamine, dimethylamine, etc.

The e-chloro-3-nitrobenzenesulfonylchloride employed above was preparedas follows: 245 g. of 4-chloro-3-nitrobenzene sodium sulfonate and 460g. of ohlorosulfonic acid were heated at 135 to 140 C. for 6 hours. Whencooled, the mixture was poured into ice water and the sulfonylchlorideseparated out as a white crystalline compound melting at 101 to 102 C.,after filtering, washing with water and drying in the air.

The pyrazolone compounds containing an esterified carboxyl group in the3-position can be prepared by esterifying a 3-carboXy-5-pyrazolone withan alcohol in the presence of a mineral acid such as hydrogen chloride,in accordance with the method of Rothenburg, Berichte 26, 2053 (1893).Alcohols such as methanol, ethanol, npropanol, isopropanol, n-butanol,ethylene glycol, diethylene glycol, triethylene glycol, propyleneglycol, fl-methoxyethanol and diethylene glycol monoethyl ether can beemployed, for example.

The 3-carboxy-5-pyrazolones are formed by hy-.

drolyzing the corresponding 3-carbethoxy-5-pyrazolones which, in turn,are formed by the interaction of oxalacetic ester with hydrazine orhydrazines in which one of the hydrogens is replaced by an alcoholradical. See Rothenburg, Berichte 25, 3441 (1892), and Berichte 26, 1719(1893). The 3-carbamyl-5-pyrazolones can be prepared by condensing3-carbomethoxy-5-pyrazolone with ammonia or primary or secondaryaliphatic amines in a sealed tube at 100 to 120 C., in accordance withthe process of Rothenburg, J. prakt. Chem. (2) 51, 43 (1895).Methylamine, ethylamine, n-propylamine, isopropylamine,pmethoxyethylamine, {3 ethoxymethoxyethylamine, dimethylamine,diethylamine, ethylmethylamine, diethanolamine, ay-dihydroxypropyhethylamine or ditetrahydrofurfurylamine can be employed, for example.

The new azo compounds of our invention are 6 of 'g'reatest utility forthe coloration of textile materials comprising organic derivatives ofcellulose. However, they may be used for the coloration of non-vegetabletextile fibers, in general. Thus, they can be usedto color organicderivatives of cellulose, silk, wool, nylon, vinyl acetatevinylchloridecopolymers, and protein synthetic wools, also cellulose esterand cellulose ether lacquers, as well-as lacquers from vinyl compoundscan be colored. The coloration produced by our new azo compounds isgenerally greenish yellow.

Typical organic derivatives of cellulose that can be colored with ournew azo compounds include the hydrolyzed, as well as the unhydrolyzed,cellulose carboxylic esters, such as cellulose acetate, cellulosepropionate and cellulose butyrate, and the hydrolyzed, as well as theunhydrolyzed, mixed cellulose carboxylic esters, such as celluloseacetate propionate and cellulose acetate butyrate, and the celluloseothers, such as methyl cellulose, ethyl cellulose and benzyl cellulose.

The azo compounds of our invention are for the most part relativelyinsoluble in water and, accordingly, they may be advantageously directlyapplied to the textile material undergoing coloration in the'form of anaqueous suspension which can be prepared by grinding the dye to a paste,in the presence of a sulfonated oil soap, or other suitable dispersingagent and dispersing the resulting paste in water. In some instances thecompounds may possess suflicient solubility in water to render the useof a dispersing agent unnecessary. Generally speaking, however, the useof a dispersing agent is desirable.

Direct dyeing operations can, with advantage, be conducted attemperatures of about 75 to 0., but any suitable temperature may beused. Thus the textile material to bedyed or colored is ordinarily addedto the dyebath at a temperature lower than that at which the mainportion of the dyeing is to be eifected, e. g., a temperature of from 45to 55 C. Following this the temperature is raised to that selected forcarrying out the operation. The temperature at which the process iscontinued may vary somewhat, depending upon the particular materialundergoing coloration. As understood by those skilled in the art, theintensity of dyeing can be varied by varying the proportion of dye tothe material undergoing preparation. Generally speaking, 1 to 3 per centby weight of the dye to material is employed, although any desiredproportions can be used.

Suitable dispersing agents are disclosed in U. S. Patent 2,115,030,issuing April 26, 1938. The process disclosed in the aforesaid patentfor the dyeing of cellulose acetate can be used in applying the dyes inthe present invention to cellulose acetate. While a satisfactory methodfor dyeing has been disclosed herein, it will be understood that anyother suitable methods for dyeing the non-vegetable textile materialsnamed herein can be employed. Lacquers may be colored with the dyecompounds of our invention by the methods customarily employed in thelacquer art.

The term nylon is intended to describe a linear polyamide resin such asset forth in United State Patent 2,071,250, dated February 16, 1937. Theterm aliphatic alcohol radical is intended to mean any radical derivablefrom an aliphatic alcohol by dropping the OH group, e. g., ethyl fromethyl alcohol, allyl from allyl alcohol, tertiary butyl from tertiarybutyl alcohol, etc.

What we claim as our invention and desire to 7 be secnred by LettersPatent of the United States Thefollowing references are of record in the10 659,267 file of this patent:

UNITED STATES PATENTS Name Date Schmid et a1. Feb. 3, 1931 Montmollin eta1. Oct. 20, 1931 V FOREIGN PATENTS Country Date Great Britain Jan. 16,1940 France Mar. 15, 1937 France Feb. 4, 1929 Germany Aug. 20, 1931

